Jalal al-Gaood, one of the tribal leaders the U.S. has been cultivating in hopes of rolling back extremists in Iraq, grimly describes how his hometown in Anbar province was forced to surrender this week to fighters from the Islamic State.

The extremists were moving Wednesday toward Gaood's town of Al-Zwaiha, the stronghold of his Albu Nimr clan just east of the Euphrates River. The attacking force had roughly 200 fighters and about 30 armed trucks. Al-Zwaiha's defenders were running out of ammunition and food, and wondered if they should make a deal with the marauding jihadists.

Gaood, a 53-year-old businessman in Amman, talked through the night with tribal elders back home. He says he tried repeatedly to reach Gen. John Allen, who is the U.S. special envoy for Iraq and Syria, to plead for emergency help. By the time Allen got the message, it was too late. Urgent warnings that the town was about to be overrun also went to the Iraqi army commander at nearby Al-Asad air base. There was no response except for a helicopter that took surveillance pictures and then left.

In the early hours of Thursday, Gaood advised the local leaders they had no alternative but to negotiate a truce. Before dawn, a convoy left for Haditha, to the north, with 60 cars carrying local police, soldiers and former members of the U.S.-created tribal militia known as the "Awakening." If they had stayed in the town, they would have been massacred when the extremists took control.

"This morning, everything is finished," Gaood told me sadly Thursday at his office here in Amman, Jordon. The Islamic State now controls the town, which straddles a strategic highway. The extremists' domination of the entire province is one step closer.

What makes this story chilling is that Gaood was one of the Sunni leaders the U.S. was hoping could organize resistance in Anbar. He was one of two dozen Iraqi tribal elders whom Allen met when he visited in early October. Gaood says he warned then that without urgent help, "We are going to have to give up the fight."

"Gen. Allen said, 'I will put you in touch with someone in Centcom.' But it never happened," Gaood says.

Military campaigns often start slowly, and that has certainly been the case with President Barack Obama's pledge to "degrade and ultimately destroy" the Islamic State. When Allen visited tribal leaders in Amman, he cautioned that he was in "listening mode" while the U.S. prepared its strategy. The U.S. presentation was "vague," says Gaood. "Every time the Iraqis meet with Americans, they just take notes."

Sitting next to Gaood during the interview is Zaydan al-Jibouri, a 50-year-old sheik of another leading tribe. He frankly admits that his fighters have joined ex-Baathists and former military officers in siding with the Islamic State. "Why do you blame us in Anbar for joining ISIS [the Islamic State]?" he asks. "The ones who went with ISIS did so because of persecution" by the Shiite-led government of former Prime Minister Nouri al-Maliki.

"The Sunni community has two options," Jibouri continues. "Fight against ISIS and allow Iran and its militias to rule us, or do the opposite. We chose ISIS for only one reason. ISIS only kills you. The Iraqi government kills you, and rapes your women." That sectarian rage and hunger for vengeance appear to animate Sunnis across Iraq.

Jibouri explains that the Islamic State was able to mobilize so quickly because it had planted "sleeper cells" in the Sunni regions. These hidden agents are mostly under 25; they grew up in the years of the insurgency and American occupation, watching as their fathers were killed or taken off to prison. "These men were brought up in the culture of vendetta and revenge," he says.

Gaood agrees that when the jihadists swept into the nearby town of Hit, 1,000 of these sleepers suddenly appeared, shattering local security.

If there's a ray of hope in the chilling accounts provided by Gaood and Jibouri, it's that even a man who says he's siding with the Islamic State still says he wants U.S. help, so long as it comes with protections for Iraq's Sunni community. "We want to create a strategic relationship with the Americans," Jibouri says, arguing that such a political deal is "the light at the end of the tunnel."

Yet when asked about the U.S. plan to create a national guard for the Sunnis, Jibouri scoffs that it's "wishful thinking" because Iraq's Shiites and Kurds will never agree. Until Sunni rights are respected, he says, "we will not allow the world to sleep."